Tension-responsive control



Dec. 25, 1956 D. B. RUSH 2,

TENSION-RESPONSIVE CONTROL Filed July 9, 1953 F Z. INVENTOR.

ATTOF/VFK United States Patent TENSION -RESPONSIVE CONTROL Dale B. Rush,Columbus, Ind., assignor, by mesne assign ments, to The RelianceElectric and Engineering Company, Cleveland, Ohio, a corporation of OhioApplication July 9, 1953, Serial No. 367,043

16 Claims. (Cl. 139-110) The present invention relates to a drive for astorage roll for flexible material, and the primary object of theinvention is to provide a mechanism which, in response to tendenciestoward variation in a condition in a length of such material, such as,for instance, tension, will automatically vary the speed at which such astorage roll is driven, either for winding or unwinding of the material,in order to maintain such condition against substantial effectivevariation.

The invention is particularly designed for use, and has been illustratedand will be described in connection, with a loom beam let-off drive; andparticularly it is an object of the invention to place the shiftableelement of a variable-speed transmission, connected to drive the unwindroll of a loom, under the domination of the conventional Whip roll of aloom.

To the accomplishment of the above and related objects, my invention maybe embodied in the form illustrated in the accompanying drawings,attention being called to the fact, however, that the drawings areillustrative only, and that change may be made in the specificconstruction illustrated and described, so long as the scope of theappended claims is not violated.

Fig. l is a side elevation of a control constructed in accordance withthe present invention, assembled with a beam let olf mechanism,fragmentarily and somewhat diagrammatically illustrated; and

Fig. 2 is an end elevation thereof.

Referring more particularly to the drawings, it will be seen that I haveshown a frame in which is journalled a shaft 11 upon which is carriedthe conventional unwind roll 12, familiarly found in loom construction.A mass 13 of flexible material such as, for instance, warp yarns isshown wound upon the roll 12; and the parts are shown, in solid lines,at a time in the cycle of the suggcsted machine, very shortly after theinitiation of an unwinding operation. It will be seen that the materialis led frornthe mass 13 in a section 14 which is always tangent to theeffective surface of the mass 13 (sometimes referred to as the eifectivesurface of the storage roll) and, after passing over the whip roll,later to be described in detail, extends in a run 16 to mechanism,suggested at 15, through which the material is forwarded at a constantlineal velocityto a point of use (not shown).

A trackway 17 which may take the form of a pair of parallel,horizontalracks, is supported upon the frame 10 (which may be a part of theconventional loom frame) above the axis of the roll 12, said trackwayextending in a direction transverse to the axis. Wheels 18, which may becogs, as shown, support an axle 19 upon said trackway 17 for movementtherealong; and a roller 20 is supported upon the axle 19 for freerotation about the axis thereof. The assembly 18, 19, 20 comprises, ofcourse, the conventional whip roll.

. An arm 21 is mounted for oscillation about a fixed axis 22 whichpreferably coincides with the axis of the shaft 11. In the illustratedembodiment. of the invention, said .arm is actually mounted upon aprojection of said shaft; the arm being free, however, for oscillationwith said shaft. The arm 21 projects into proximity with the trackway 17and, at its outer end, is bifurcated to define a slot 23, elongated inthe direction of length of the arm, and freely receiving a projectingend of the axle 19. Thus, the roll 20 is operatively connected to thearm 21, whereby movement of said roller along the trackway 17 will beaccompanied by oscillation of the arm 21 about its journal axis 22. Acable 24 has one end anchored to the arm 21, passes over a pulley 25,and supports a weight 26, whereby said arm is yieldably biased to holdthe roller 20 at the left-hand end of the trackway 17, as viewed in Fig.l.

It will be seen that the roller 20 bears against the inner surface ofthe material 14 within that sector which is defined between the currentpoint of tangency .of section 14 with the effective surface of the roll,and a vertical plane including the axis of the roll 12.

A shaft, indicated at 27, is driven through suitable means (not shown)at a constant ratio with respect to the material-forwarding means 15. Abevelled gear 28 on the shaft 27 meshes with a bevelled gear 29 on ashaft 30 suitably supported upon an axis parallel with the axis of theshaft 11; and a first resiliently expansible V-pulley, indicatedgenerally by the reference numeral 31, is mounted to rotate upon theaxis of the shaft 30.

The pulley 31 comprises a coned. disc 32 axially fixed with respect tothe shaft 30 and a mating coned disc 33 mounted for axial reciprocationrelative to the shaft 30, and resiliently urged toward the disc 32 by aconventional spring unit 34.

A sprocket 35 is fixed to the shaft 11 and is drivingly connected by achain 36, with a sprocket 37 on the output shaft 38 of reducing gear 39.The input shaft 40 of the gear 39 carries a resiliently expansibleV-pulley, indicated generally by the reference numeral 41, andcomprising a coned disc 42 fixed to the shaft 40 and a mating coned disc43 axially shiftable relative to the shaft 40 and resiliently urgedtoward the disc 42 by a conventional spring unit 44.

Upon a bracket 45, mounted in a horizontal plane between the axes of thepulleys 31 and 41, a bearing 46 pivotally supports the intermediateportion of a bellcrank lever 47 for oscillation about an axis parallelwith, but oflfset from, the plane common to the axes of the pulleys 31and 41. One arm 48 of the lever 47 supports a jack-shaft 49 upon whichare mounted two fixed-di ameter pulleys 56 and 51. The pulleys 50 and 51are connected to rotate together; and this connection is mostconveniently provided by drivingly connecting both pulleys to thejack-shaft 49. A belt 52 provides a driving connection between thepulley 31 and the pulley 50, while a belt 53 provides a drivingconnection between the pulleys 51 and 41. i

To the other arm 54 of the bell-crank lever 47 is connected one end of alink 55, the other end of which ispivotally connected, as at 56, at anintermediate point in the arm 21.

When a loaded storage roll 12 is mounted in the frame 10, the arm 21under the influence of the weight 26, will be in its extremecounter-clockwise position, in which the roller 20 on the axle 19 willbe at the extreme left-hand end of the track 17. The end of the materialon the roll will now be carried over the whip roll 20 and to theforwarding means 15, and thence to a point of use. When the forwardingmeans 15 is energizedythe shaft 27 will likewise be driven. The partsare so proportioned and designed that, under these conditions, the roll12 will be driven at an angular velocity such as to maintain apredetermined degree of tension in the run 16. As material is withdrawnfrom the mass 13, the effective diameter of the unwind roll 12 isdecreased. Since the roll is turningat a constant angular velocity underthe driving influence of the shaft 27 through the variable speedtransmission comprising the pulley 21, the pulleys 5t) and 51 and thepulley 41, there is a tendency for the tension in the run 16 of thematerial to increase. At the same time, the point of tangency of thesection 14 with the effective surface of the mass 13 moves graduallytoward the right, as viewed in Fig. l. The combined effect of these twotendencies will be to increase the horizontal component of the forceexerted upon the roller 20 by the material; whereby the tendency of theweight 26 is overcome, and the whip roll 20 will be moved toward theright along the trackway 17. Thereby, through the link 55, thebell-crank lever 47 will be turned in a clockwise direction. Suchmovement of the lever will tend to move the jack-shaft 49 toward thepulley 31 and away from the pulley ll. This will tend to produce slackin the belt 52; but the spring unit 34 will, of course, move the disc 33toward the disc 32, thus squeezing the belt 52 outwardly between thediscs 32 and 33, to increase the effective diameter of the pulley 31. Atthe same time, as the pulley Slmcves away from the pulley 41, the belt53 will be pulled more deeply into the groove between the discs 42 and43, forcing the disc 43 away from the disc 42, against the tendency ofthe unit 44, and decreasing the effective diameter of the pulley 41. Theincrease in the effective diameter'of the pulley 31 will, of course,result in increasing the speed at which the jack shaft 49 will bedriven; and the decrease in the effective diameter of the pulley 41 willresult in increasing the speed of the shaft relative to the speed of thejack-shaft 49. Thus, as the whip roll 20 moves gradually toward theright, as viewed in Fig. l, the speed of the shaft 11 will be graduallyincreased. Obviously, the proportions of the several parts can be soconstructed that the increase in the speed of the shaft 11 willprecisely compensate for the diminution in the effective diameter of themass 13, to maintain constant tension upon the run 16, which iscontinuously forwarded, at a constant lineal speed, by the forwardingmeans 15.

It will be clear that the illustrated mechanism could be used, also, ina winding operation. In such case, the material-forwarding means 15would, of course, move the material toward, instead of away from, thestorage roll 12 at constant velocity; and the control mechanism wouldoperate to reduce the angular velocity of the roll 12, progressively,under the domination of variation, or rather tendencies towardvariation, in the tension in the section 16 of the material. The whiproll 20 would move progressively from its dotted line position towardits solid line position,

as viewed in Fig. 1, to move the arm 21 progressively in acounter-clockwise direction, during such winding opera tion. Thereby,the lever 47 would be progressively moved in a counter-clockwisedirection to shift the jack-shaft 49 away from the pulley 31 and towardthe pulley 41, to reduce, progressively, the effective diameter of thepulley 31 and to increase, progressively, the effective diameter of thepulley 41.

I claim as my invention:

1. Means for automatically controlling the rate of rotation of a storageroll for flexible material, comprising in combination with such a roll,a length of flexible material wound on said roll, means for forwardingsaid material relative to said roll, rotary means driven at a constantratio with respect to. said forwarding means, variable-speedtransmission means connecting said rotary means to drive said roll andcomprising an input shaft connected to be driven from said rotary means,an output shaft connected to drive said roll, an expansible V-pulley oneach of said shafts, edge-active belt means providing a drivingconnection between said pulleys, and an element shiftable to varyinversely the effective diameters of said pulleys, an arm mounted foroscillation about a fixed axis in a common plane with the axis of saidroll, means operatively engaging said arm and bearing against the innersurface of said material at a point within the sector defined betweenthe current point of tangency of said material with the effectivesurface of said roll and a plane including the axis of said roll andnormal to the plane of movement of said material, means yieldinglyresisting movement of the arm in response to an increase in the tensionon that reach of the material between the forwarding means and saidmeans bearing against the material, and means connecting said arm toshift said shiftable element.

2. Means for automatically controlling the rate of rotation of a storageroll for flexible material comprising, in combination with such a roll,a length of flexible material wound on said roll, means for forwardingsaid material at constant lineal velocity, rotary means driven at aconstant ratio with respect to said forwarding means, variable-speedtransmission means connecting said rotary means to drive said roll, saidtransmission means including an element shiftable oppositely to varyoppositely the output speed of said transmission means, an arm mountedfor oscillation about the axis of said roll, a trackway spaced from saidaxis, disposed in a plane substantially parallel with said axis andextending in a direction transverse to the direction of length of saidaxis, a bearing member supported on said trackway for movementtherealong, bearing against the inner surface of said material at apoint within the sector defined between the current point of tangency ofsaid material with the effective surface of said roll and a planeincluding the axis of said roll and normal to the plane of movement ofsaid material, said bearing member being operatively connected with saidarm, said arm being yiel-dably biased away from said normal plane andtoward said current point of tangency, and means connecting said arm toshift said shiftable element.

3. Means for automatically controlling the rate of rotation of a storageroll for flexible material comprising, in combination with such a roll,a length of flexible material wound on said roll, means for forwardingsaid material at constant lineal velocity, rotary means driven at aconstant ratio with respect to said forwarding means, a pulley driven bysaid rotary means, a second pulley spaced from said first-named pulleyand mounted on an axis parallel with the axis of said first pulley, ajack shaft, means supporting said jack shaft between said first andsecond pulleys upon an axis parallel with the axes of said pulleys forbodily movement toward and away from said first pulley, a third pulleyand a fourth pulley drivingly mounted on said jack shaft, a first belttrained over said first pulley and over said third pulley, a second belttrained over said second pulley and over said fourth pulley, one of thepulleys engaged by each of said belts being an expansible V-pulley,means connecting said second pulley to drive said roll, an arm mountedfor oscillation about the axis of said roll, a trackway spaced from saidaxis, disposed in a plane substantially parallel with said axis andextending in a direction transverse to the direction of length of saidaxis, a bearing member supported on said trackway for movementtherealong, bearing against the inner surface of said material at apoint within the sector defined between the current point of tangency ofsaid material with the effective surface of said roll and a planeincluding the axis of said roll and normal to the plane of movement ofsaid material, said bearing member being operatively connected with saidarm, said arm being. yieldably biased away from said normal plane andtoward said current point of tangency, and means connecting said arm toshift said jack shaft.

4. The control means of claim 3 in which said means supporting said jackshaft comprises a lever mounted to swing upon an axis parallel with saidpulley axes and eccentric with respect to said jack shaft axis.

5. The control means of claim 3 in which said first pulley and saidsecond pulley are resiliently-expansible V-pulleys and said third andfourth pulleys are fixeddiarneter V-pulleys.

'6. Means for automatically controlling the rate of rotal l v tion of astorage roll for flexiblematerial comprising, in combination with such aroll, a length of flexible material wound on said roll, means forforwarding said material at constant lineal velocity, rotary meansdriven at a constant ratio with respect to said forwarding means, aresiliently-expansible V-pulley driven by said rotary means, a secondresiliently-expansible V'pulley spaced from said first-named pulley andmounted on an axis parallel with the axis of said first pulley, a jackshaft positioned between said first and second pulleys upon an axisparallel to the axes of said pulleys, a third pulley and a fourth pulleydrivingly mounted on said jack shaft, a first belt trained over saidfirst pulley and over said third pulley, a second belt trained over saidsecond pulley and over said fourth pulley, an arm mounted foroscillation about the axis of said roll, a trackway spaced from saidaxis, disposed in a plane substantially parallel with said axis andextending in a direction transverse to the direction of length of saidaxis, a bearing member supported on said trackway for movementtherealong, bearing against the inner surface ofsaid material at a pointwithin the sector defined between the current point of tangency of saidmaterial with the effective surface of said roll and a plane includingthe axis of said roll and normal to the plane of movement of saidmaterial, said bearing member being operatively connected with said arm,said arm being yieldably biased away from said normal plane and towardsaid current point of tangency, means shiftable oppositely to expand oneor the other of said resiliently-expansible V-pulleys selectively whilepermitting contraction of the other, means connecting said arm to shiftsaid shiftable means, and means connecting said second pulley to drivesaid roll.

7. The combination with a loom beam let-off including an unwind roll, awhip roll supported to travel on a substantially horizontal trackway, alength of flexible material wound on said unwind roll, and means forwithdrawing said material from said unwind roll, said material extending from said unwind roll over said whip roll and thence to saidwithdrawing means and said whip roll having its axis always within thesector between the current point of tangency of said material with theeffective surface of said unwind roll and a substantially vertical planeincluding the axis of said unwind roll, of a tension-responsive drivefor said unwind roll comprising rotary means driven at a constant ratiowith respect to said withdrawing means, variable-speed transmissionmeans connecting said rotary means to drive said unwind roll andcomprising an input shaft connected to be driven from said rotary means,an output shaft connected to drive said roll, an expansible V-pulley oneach of said shafts, edge-active belt means providing a drivingconnection between said pulleys, and an element shiftable to varyinversely the effective diameters of said pulleys, and means connectingsaid whip roll to shift said shiftable element to increase the outputspeed of said transmission means as said whip roll travels toward saidvertical plane.

8. The combination of claim 7 in which said means connecting said whiproll to shift said shiftable element comprises an arm mounted foroscillation about the axis of said unwind roll, means yieldably biasingsaid arm toward said current point of tangency and away from saidvertical plane, said Whip roll having a driving connection with saidarm, and means providing a driving connection between said arm and saidshiftable element.

9. The combination with a loom beam let-off including an unwind roll, awhip roll supported to travel on a substantially horizontal trackway, alength of flexible material wound on said unwind roll, and means forwithdrawing said material from said unwind roll, said material extendingfrom said unwind roll over said whip roll and thence to said withdrawingmeans and said whip roll having its axis always within the sectorbetween the current point of tangency of said material with theeffective surface of said unwind roll and a substantially vertical planeincluding the axis of said unwind roll, of a tension-responsive drivefor said unwind roll comprising rotary means driven at a constant ratiowith respect to said withdrawing means, variable-speed transmissionmeans comprising a pulley driven by said rotary means, a. second pulleyspaced from said first-named pulley and mounted on an axis parallel withthe axis of said first pulley, a jack shaft, means supporting said jackshaft between said first and second pulleys upon an axis parallel withthe axes of said pulleys for bodily movement toward and away from saidfirst pulley, a third pulley and a fourth pulley drivingly mounted onsaid jack shaft, a first belt trained over said first pulley and oversaid third pulley, a second belt trained over said second pulley andover said fourth pulley, one of the pulleys engaged by each of saidbelts being, an expansible V-pulley, an element shiftable oppositely tovary oppositely the output speed of said transmission means, an armmounted for oscillation about the axis of said unwind roll, meansyieldably biasing said arm toward said current point of tangency andaway from said vertical plane, said whip roll having a drivingconnection with said arm, means providing a driving connection betweensaid arm and said shiftable element, means connecting said shiftableelement to shift said jack shaft toward and away from said first pulley,means connecting said whip roll to shift said shiftable element toincrease the output speed of said transmission means as said whip rolltravels toward said vertical plane, and means connecting said secondpulley to drive said unwind roll.

10. The combination of claim 9 in which said means supporting said jackshaft comprises a lever mounted to swing upon an axis parallel with saidpulley axes and eccentric with respect to said jack shaft axis.

11. The combination of claim 9 in which said first pulley and saidsecond pulley are resiliently-expansible V-pulleys and said third andfourth pulleys are fixeddiarneter V-pulleys.

12. The combination with a loom beam let-off including an unwind roll, awhip roll supported to travel on a substantially horizontal trackway, alength of flexible material wound on said unwind roll, and means forWithdrawing said material from said unwind roll, said material extendingfrom said unwind roll over said whip roll and thence to said withdrawingmeans and said whip roll having its axis always within the sectorbetween the current point of tangency of said material with theeffective surface of said unwind roll and a substantially vertical planeincluding the axis of said unwind roll, of a tension-responsive drivefor said unwind roll comprising rotary means driven at a constant ratiowith respect to said withdrawing means, variable-speed transmissionmeans comprising a pulley driven by said rotary means, a second pulleyspaced from said first-named pulley and mounted on an axis parallel withthe axis of said first pulley, a jack shaft, means supporting said jackshaft between said first and second pulleys upon an axis parallel withthe axes of said pulleys for bodily movement toward. and away from saidfirst pulley, a third pulley and a fourth pulley drivingly mounted onsaid jack shaft, a first belt trained over said first pulley and oversaid third pulley, a second belt trained over said second pulley andover said fourth pulley, one of the pulleys engaged by each of saidbelts being an expansible V-pulley, an element shiftable oppositely tovary oppositely the output speed of said transmission means, meansconnecting said shiftable element to shift said jack shaft toward andaway from said first pulley, means connecting said whip roll to shiftsaid shiftable element to increase the output speed of said transmissionmeans as said Whip roll travels toward said vertical plane, and meansconnecting said second pulley to drive said unwind roll.

13. The combination of claim 12 in which said means supporting said jackshaft comprises a lever mounted to swing upon an axis parallel with saidpulley axes and eccentric with respect to said jack shaft axis.

14. The combination of claim 12 in which said first 7 pulley and'saidsecond pulley are resiliently-cxpansible V-pulleys and said third andfourth pulleys are fixeddiameter 'V-pulleys.

15.'The combination with a loom beam let-off including an unwind roll, awhip roll supported to travel on a substantially horizontal trackway, alength of fiexible material wound on said unwind roll, and means forwithdrawing said material from said unwind roll, said material extendingfrom said unwind roll over said whip roll and thence to said withdrawingmeans and said whip roll having its axis always within the sectorbetween the current point of tangency of said material with theefiective surface of said unwind roll and a substantially vertical planeincluding the axis of said unwind roll, of a tension'respon sive drivefor said unwind roll comprising rotary means driven at a constant ratiowith respect to said withdrawing means, a first resiliently-expansiblell-pulley driven by said rotary means, a second resiliently-expansibleV-pulley spaced from said first pulley and mounted on an axis parallelwith the axis of said first pulley, a bell-crank lever intermediatelysupported to swing about an axis parallel with, but offset from theplane common to the axes of said pulleys, a jack shaft carried by onearm of said lever for rotation about an axis disposed between theaxes'of said pulleys and parallel therewith, two fixed diameter pulleys,mounted on said jack shaft and connected for joint rotation, a beltproviding a driving connection between said first pulley and one of saidjack shaft pulleys, a second belt providing a driving connection betweenthe other of said jack shaft pulleys and said second pulley, meansproviding a driving connection between said second pulley and saidunwind roll, and means providing a driving connection between said whiproll and the other arm of said lever to shift said jack shaft towardsaid first pulley as said whip roll travels toward said vertical plane.

16. The combination With a loom beam let-oif including an unwind roll, awhip roll supported to travel on a substantially horizontal trackway, alength of flexible material wound on said unwind roll, and means forwithdrawing said material from said unwind roll, said material extendingfrom said unwind roll over said whip roll and thence to said withdrawingmeans and said whip roll having its axis always within the sectorbetween the current point of tangency of said material with theeffective surface of said unwind roll and a substantially vertical planeincluding the axis of said unwind roll, of a tension-responsive drivefor said unwind roll comprising rotary means driven at a constant ratiowith respect to said withdrawing means, a first resiliently-expansibleV-pulley driven by said rotary means, a second resiliently-expansibleV-pulley spaced from said first pulley and mounted on an axis parallelwith the axis of said first pulley, a bell-crank lever intermediatelysupported to swing about an axis parallel with, but offset from theplane common to the axes of said pulleys, a jack shaft carried by onearm of said lever for rotation about an axis disposed between the axesof said pulleys and parallel therewith, two fixeddiameter pulleys,mounted on said jack shaft and connected for joint rotation, a beltproviding a driving connection between said first pulley and one of saidjack shaft pulleys, a second belt providing a driving connection betweenthe other of said jack shaft pulleys and said second pulley, meansproviding a driving connection between said second pulley and saidunwind roll,-an arm mounted for oscillation about the axis of saidunwind roll, said whip roll being operatively connected to said arm toshift the same as said whip roll travels on said trackway, meansyieldably biasing said arm toward said current point of tangency andaway from said vertical plane, and a link connecting the other arm ofsaid lever with an intermediate point on said oscillable arm.

ReferenccsCited in the file of this patent UNITED STATES PATENTS2,103,200 Brown Dec. 21, 1937 2,175,551 Perry Oct. 10, 1939 2,398,547Moessinger Apr. 16, 1946 2,581,328 Malcom Jan. 1, 1952 2,608,741 ReevesSept. 2, 1952 2,664,724 Lambach Jan. 5, 1954 FOREIGN PATENTS 235,025Switzerland Nov. 15, 1944

